Method and system for ventilating and conditioning auditoriums and the like



Nov. 20, 1934. w. H. CARRIER METHOD AND SYSTEM FOR VENTILATING ANDCONDITIONING AUDITORIUMS AND THE LIKE Original Filed June 22 1927 2Sheets-Sheet l fjlZil VI ZZ W -Sheet 2 W. H. CARRIER METHOD AND SYSTEMFOR VENTILATING AND CONDITIONING AUDITORIUMS AND THE LIKE Original FiledJune 22, 1927 2 Sheets I :l|l||..||||H HHHIIH HUXMIIIIIIIIIIIIIIH Hlmwllllllh IIIIWII HHIHHH Nov. 20, 1934.

Patented Nov. 20, 1934 UNITED STATES METHOD AND SYSTEM FOR VENTILATINGAND CONDITIONING AUDITORIUMS AND THELIKE Willis H. Carrier, Essex Fells,N. 1., assignor to Carrier N. J.

Engineering Corporation. Newark,

Original application June 22, 1927, Serial No. 200,665. Divided and thisapplication August 12, 1930, Serial No. 474,772

Claims.

This invention relates to the heating, cooling and ventilation ofauditoriums or theaters and other places of assembly which are analogousto theaters as regards the requirements and equipment for theventilation and air conditioning thereof. The word auditorium ashereinafter employed is intended to designate such places or rooms.

This application is a division of my copending application Serial No.200,665, filed June 22, 1927, which has matured into Patent 1,775,749,patented Sept. 16, 1930, and reissued Aug. 7, 1934 as Re. 19,263.

It is desirable that the air supplied to such places for ventilationpurposes be conditioned so as to provide the greatest comfort for thepeople assembled therein, and the temperature and humidity of theconditioned air necessary to provide this comfort will vary withexterior atmospheric conditions and the number of people assembled.

Heretofore, varioussystems have been devised for heating, ventilatingand cooling such places, but such systems have been designed with a viewto carefully avoiding noticeable movements of air in the auditorium inorder to avoid the possibility of any drafts striking the peoplecongregated, and prevent the people from being sensible to pronouncedatmospheric changes. It is also a matter of common knowledge that peop'eobject to drafts against the back of their heads or persons while aslight movement of the air against their faces is enjoyed, and thatdrafts of cold air around the feet are objectionable.

In the systems heretofore employed for ventilating, heating and coolingsuch places, it has been the practice to withdraw air from the roomthrough suitable ducts or passages, mix it, if desired, with outsideair, and return the mixed air to the auditorium, the relatively largevolumes of air which are withdrawn and returned to the auditorium oradmitted from the, outside, or both, being conditioned prior toadmission to the auditorium. In order to avoid drafts in the auditorium,the tempering of dehumidified air during the conditioning operation wasaccomplished by mixing it with the other air exteriorly of theauditorium, and then admitting the tempered mixture at a very lowvelocity to the auditorium by means of numerous ducts placed so as todistribute the air as evenly as possible throughout the auditorium.

In those prior systems. .the relatively large amount of tempered airwhich must be handled at a low velocity requires the provision ofrelatively large blowers or fans and operating motors, and an extensivesystem of large supply and return conduits that are expensive anddimcult to install and conceal in the building structure, especially inbuildings such as theaters which are usually of elaborate architecturaldesign and ornamentation.

With the positive circulation created by the ejector nozzles of thisinvention, it becomes. unnecessary to provide an elaborate distributionof the points at which air is returned to the air conditioning apparatusor removed from the auditorium,- to avoid dead corners or dead spots andtherefore, the return system can be greatly simplified, and a greatsaving efiected in the cost of the return or recirculation system.

An object of this invention is to provide an improved, practical andefiicient method and system for cooling, ventilating and heatingauditoriums and the like in which people congregate in considerable andvarying numbers; with which desirable temperature and relative humidityconditions may be maintained in the enclosure regardless of the numberof people therein or external atmospheric conditions; and with whichthere will be no discomfort to the people assembled in such places dueto the operation of the improved method and system of heating, coolingand ventilation.

A further object of this invention is to provide an improved method andsystem for ventilating auditoriums and the like in which the size ofapparatus required for conditioning the air and circulating the samewill be relatively small and compact, in which the total number and sizeof the air ducts may be considerably reduced and the ducts more readilyconcealed within the structure.

When properly introduced, the small volume of air handled by theapparatus of this application will induce a secondary circulationamounting to three or four times the volume of the primary circulation,so that for an equal effect in the auditorium, air conditioningapparatus and ducts of from one fourth to one fifth normal size can beused. Furthermore, the mixture of from three to four parts of room airwith one part of cooled air warms the dehumidified air, so that beforecoming in contact with any of the people in the audience, itstemperature is raised to an amount equal. to three fourths or fourfifths of its original depression below the theater temperature.

A still further object of the invention is to provide an improved systemor apparatus for heating, cooling and ventilating auditoriums and thelike which is relatively simple and inexpensive in both constructionand-operation, one of the important features of this improved systembeing the creation of a definite controlled circulation of air inthetheater or auditorium.

Various other objects and advantages will be apparent from the followingdescription of two embodiments of the invention, and the novel featureswill be particularly pointed out hereinafter in connection with theappended claims.

In the accompanying drawings: f Fig. 1 is a sectional elevation of anauditoriu without a balcony, in which the ventilation, heating andcooling is accomplished in accordance with this invention.

Fig. 2 is a sectional plan of the same.

In the illustrated embodiment of the invention,

the building has an auditorium or room 1 in which the people assemble,with a proscenium arch 2 at one end leading to the stage. Such anauditorium has a relatively high ceiling with a deep space between theceiling and the section occupied by the audience. The entrance to theauditorium may be through one or more passages or doorways 3 at the endopposite from the stage, and the auditorium may also be provided withthe usual emergency exit doors 4.

Air conditioning apparatus 5 may be located in any suitable, availablespace 6 in the building, such as in the basement under the rear of theauditorium, as shown in Fig. l, or on the roof, or in the upper rooms,or partially in the upper room or on the roof and partially in thebasement, the exact place selected depending upon expediency and theparticular details of the structure or building in which the auditoriumis provided.

A blower or fan 7 for causing the circulation of air in and through theroom 1 is preferably connected at its inlet side to the-outlet side ofthe air conditioning apparatus 5, and at its outlet side is connected toa duct 8 which extends to a point adjacent the ceiling of the auditoriumand then transversely across the room at a point adjacent the ceiling. Aplurality of nozzles 9 are provided on the transverse stretch of theduct 8 through which the air is delivered into the room so as to directthe air from the duct 8 at a high velocity into the room in therelatively deep space just below the ceiling, that-is, at a point wellabove the lower section of the room which the people occupy.

The duct 8 equipped with the discharge ndz-- zles is preferably encasedin the cornice or other part of the wall or ceiling of the room so as tobe hidden from view. The nozzles can project from the duct and terminatesubstantially flush with the inner surface of the cornice or wall, asshown in Fig. 1, where sufficient space is aiforded in the wall for thisconstruction. The nozzles can be of sufllcient length to give therequired directional control of the discharging air jets.

While the duets. with the nozzle 9 may be arranged at different pointsspaced apart in the direction in which they open for larger rooms, theypreferably, particularly for rooms of smaller or moderate size, arearranged in a row extending substantially entirely across one lateralwall of the room, as shown'in-Fig, 2, so that a plurality of highvelocity jets of air will be directed in the same direction across theroom in the upper or unoccupied part thereof. These high velocity jetsof conditioned air willbe discharged in such .di-

when the ceiling is substantially horizontal, as shown in Fig. 1, thesejets of conditioned air may be directed approximately parallel and nearthe ceiling, so that the circulation of air caused by the jets will bealong or adjacent the ceiling.

The jets act as injectors'and cause a circulation of the relativelylarger volume of air of the room therewith through theupper relativelydeep, unoccupied space 'in the room, and during and by reason of suchcirculation the injected conditioned air is intimately mixed with andtempered bythe room air which is drawn into the circulation. I Themixture is then carried through the upper or unoccupied space of theroom by the circulation caused by the high velocity injected' air, andwill descend into the lower or occupied section of the room as thecirculating air loses its velocity or approaches the side of the roomopposite from that where the conditioned air is injected. Some of themixture of air moving adjacent the ceiling will descend into the lowersection of the room as the mixture moves across the room, and all of the-air reaching the lower or occupied section of the room will move at arelatively low velocity toward the side of the room where theconditioned air was injected, soas to complete the circulation, as shownby the arrows in Fi 1.

Air may be withdrawn from the room and conducted to the air conditioningapparatus 5, conditioned'and returned to the room through nozzles 9.When the volume of air injected into the room is greater than thatwithdrawn, the air displaced by the injected air may escape from theroom through any suitablerelief outlet, such as through the entrancepassage 3, and the windows, doors and other places of leakage, sinceobviously auditoriums are never entirely air tight. Furthermore, thetoilet and rest rooms that are provided adjacent the auditorium willusually have some ventilating means for removing to some extent the airof those rooms, and part of the air of the auditorium which is displacedmay escape through those auxiliary rooms.

The air withdrawn fromthe room for conditioning and return to the roomis taken from the room at such point or points with reference to theoccupied section of the room so as to insure a circulation of thetempered mixture into this occupied section. along the. floor, the airwithdrawn for conditioning and return will preferably be taken from theroom at a point or points in or near the floor. For example, a pair ofreturn ducts l0 and 11 may be provided under the floor of the room so asto extend in a direction from front to rear, and

' locatedpreferably along the aisle spaces 12 and 13.

Openings 14 to the ducts 10 and 11 are provided through the floor of theroom at the edges of the aisle sections, and these openings mayconveniently be provided under the seats 14a in the center seat section,just at the'edge of the aisles, as shown clearly in Fig. 2. The returnopenings may be of the mushroom or aisle-hood type, or they may beregisters or grilles placed either in the floor or in the walls of theroom, near the floor line, and the return ducts may be arranged asrequired, to suit the particular arrangement of the retum-openings.

The ducts 10 and 11 connect with a mixing chamberor main passage 15opening into the inlet side of the air conditioning apparatus 5. Theconnection between the ducts 10 and 11 and the passage 1'5"leading"*tothe air conditioning apparatus may be provided with dampers or .shutters16 f The occupied section being which control the amount of airwithdrawn through the ducts 10 and 11 from the room and conducted to theair conditioning apparatus. Dampers or shutters 17 control the passageof fresh air through a fresh air inlet 17a into the mixing chamber orpassage 15. By suitably adjusting the dampers or shutters 16 and 17, therelative proportions of fresh air and return air which are conveyedthrough the chamber or passage 15 to the air conditioning apparatus maybe varied as desired. The shutters and dampers 16 and 17 may beregulated by suitable hygrometric or temperature responsive instrumentscommon to the art and disposed at suitable points.

Theair conditioning apparatus preferably includes a dehumidifying device18, such as a spray dehumidifier through which the air to be conditionedis passed and cooled, and its excess moisture removed. The liquid forthe spray of the dehumidifier may be cooled by a refrigerating device18a as usual. When necessary, on account of low relative humidities ofthe outside air in cold weather, unrefrigerated or warm water may besupplied to the spray device 18, or the necessary heat otherwisesupplied to the conditioning apparatus for raising the humidity of theair to the required dew point. The cooled and dehumidified air isconducted through a heater 19, preferably located between thedehumidifier and, the blower or circulating fan '7, so that whendesired, the temperature of the conditioned air from the device 18 maybe raised to the desired extent. In winter time it may be desirable tooperate the heater so as to increase the temperature of the injectedair, especially when, the room is being initially heated, prior to or atthe beginning of occupancy of the room by the people. By such airconditioning apparatus, the air injected into the room through thenozzles 9 may be given any desired temperature and humidity, theparticular temperature and humidity being regulated so as to provide themaximum comfort to the occupants of the room.

The nozzles 9 are disposed at the rear of the assembly room, so that thecirculation through the upper part of the room will be forwardlytherein, with the result that the circulation in the lower or occupiedsection of the room will be rearwardly. Therefore, the air moving in thereverse direction in the occupied section of the room will strike theoccupants from the front, which'is.

not objectionable to them while it would be an objection to have the aircurrent strike them from the rear. The air which moves downwardly to thefloor by the circulation in the occupied section will be heated by andreceive moisture from the people in the occupied section, with theresult that the air striking the feet of the congregated people will bethe warmest of any in the room with which thepeople may come in contact,and therefore, there will not be any discomfort to the occupants of theroom due to cold feet.

In such an installation the air will be delivered at high velocitiesthrough the nozzles forwardly into the auditorium adjacent the ceilingthereof, so that the maximum circulation in the room will be along ornear the ceiling and toward the stage. These jets of conditioned airmoving at high velocities, act like injectors and cause circulation ofthe air in the room and a mixture of the injected air and the air of theroom. The tempered mixture of air then descends and moves slowly in adirection from front to, rear in the lower or'occupied section of theroom and will be gradually withdrawn through the outlets in thefloor ofthe room.

It will be observed that the tempering of the conditioned air isobtained entirely or principally within the room itself while occupiedby the people and not exteriorly thereof, as has been heretofore thecase. Consequently, it is only necessary to handle by the mechanicalapparatus the relatively small volume of injected, dehumidified, cooledor conditioned air and not the large volume of air circulating in theroom and with which it is mixed and by which it is tempered. The volumeof air to be handled for any given size of room is therefore materiallyless with this improved system of ventilation, heating and cooling thanwith prior systems in which the mixing or tempering occurred principallyor entirely outside of the auditorium.

With this improved system it will be observed that the total lengths ofpipe or conduits required to handle the air for any given room is very"considerably reduced in comparison with that required for previoussystems, as it is not necessary to provide numerous supply openingsdis-' posed about the room in order todistribute the air uniformly tovarious parts of the room. Since a smaller volume of air is handled bymechanical apparatus in this improved system, and since the air ishandled at a high velocity, the ducts for handling the air may also bemade very much smaller than heretofore, and the blower and operatingmotor may likewise be made very much smaller, so that a considerablesaving is obtained, not only in the space occupied by the apparatus andconduits, but also in the original and maintenance costs of the smallerapparatus and conduits required.

Prior systems supplied air to the room at such low velocities, 200 to400 feet per minute, as to necessitate the handling of greatly increasedvol- 11,5 umes of air, or else create a ventilating condition amountingnearly to one of stagnation, owing to the fear of drafts upon theoccupants of the room. Where the cooled air was introduced into thelower part of the room, it caused great 12) discomfort to the feet ofthe occupants -assembled in the lower part of the room, particularly ifthere was any movement of the air. My improved system, in contrast toprior systems, discharges air from the injector nozzles into the room atvelocities usually averaging 2000 feet or more per minute, andisdesigned to create a certain amountv of circulation in the occupiedsection of the room, so as to cause the movement of air over each andevery person in the audience of suchv a velocity, temperature andhumidity condition that the sensation is pleasing rather thandisturbing. The air supplied to the room through the injector nozzles isconditioned. before, admission to the room, to a dew point andtemperature such that when it is mixed with the air in the room, themixed circulating air, when it reaches the occupants of the room willhave the required temperature and relative humidity to affordthevmaximum comfort to the people. By reason of the vigorous circulationin the upper part of the room and the uniformity of circulation in thelower part of the room, I am able to perfect uniformity of temperatureand humidity in 'all of the air which comes in con- 1!, tact with theaudience so that there will be no. discomfort of the audience, due tocold feet or chilling drafts. i

perature of the air injected through the nozzles into the room is raisedby mixing it in the upper portion of the room with the relatively largevolume of warmer air in the room before any part of the mixed air comesin contact with the people. I

The following example affords an illustration of the operation of thesystem under practical conditions. In order to maintain .the auditoriumtemperature at degreeswith a desirable relative humidity, air at about51 degrees would ordinarily be introduced into the room through theinjector nozzles. But experience has shown that it was entirelyimpractical to distribute air at 51 degrees by prior systems in a placesuch as an auditorium occupied by people. If, however, as in the presentsystem, a secondary circulation in the room is introduced by theinjected air in the ratio of one part of injected air to four parts ofroom air, the 51 degree injected air is mixed with 75 degree air of theroom, and the temperature of the mixture is 69 degrees. This mixed airat 69 degrees can be, and by this system is, distributed so as to reachpeople without causing objectionable drafts or atmospheric changes. Thismixing and temperating of the air is done in the free upper space-of theroom itself so that the air capacity, of the fan and ducts in thisinjector system under the operating conditions justabove described isone-third that of the fan and duct capacity-of systems such asheretofore used, in which the mixing of the low temperature air and theair from the room is done outside of the room in the air recirculatingapparatus. v

It will benoted that the auditorium or space as illustrated in thedrawings tapers or gradually increases in depth from one end toward theother end thereof so that the volume of air in the room per unit of roomlength gradually increases from the end having the least height towardthe end having the greatest height, and since the conditioned air isinjected into the upper portion of a part of the room of lesser depthand in a directionv toward the part of the room having greater depth,the resistance to the flow of the injected air currents progressivelydecreases commensurately with the increasing distance which the currentstravel from the injector nozzles, and the relatively small volumes ofinjected air which are delivered at relatively high velocity are adapted-to travel and move and mix with the strata of the air supplied to theinjector nozzles in order s to obtain a substantially constant dischargevelocity from the nozzles, and therefore a uniform circulation andmixture of the air in the room. When, however, the auditorium issparsely occupied, the heat and moisture produced in the auditorium bythe people is of course much less, and consequently a smaller volume ofconditioned air would be sufficient to give comfort to the few people inthe audience. But, if the same volume of dehumidified air is dischargedinto the room as when it is filled with people, heating means would benecessary to bring the dehumidifled air up to the desired temperaturefor delivery to the room. When, therefore, the auditorium is empty oronly sparsely occupied, it may be desirable to recirculate more or lessof the air withdrawn from the room and return it to the room withoutpassing it through the air conditioning device, mixing this recirculatedair with the conditioned or dehumidified air coming from the airconditioner and discharging the mixture into the room, thereby utilizingtherecirculated air to heat or temper the conditioned air, and to thisextent, saving fuel for heating the air delivered to the room.

To make this possible, a by-pass or branch duct may be provided, forinstance as shown at 40, connecting the air circulating fan with thereturn duct 10 around or outside of the air dehumidifying orconditioning device. The bypass duct 40, as shown connects with amixingchamber 41 between the dehumidifier 18 and the heater 19, andiscontrolled by a damper 42 so that the proportions of return air passedthrough or bypassed around the dehumidifier can be controlled by theoperation of the dampers 16 and 42 in accordance with the requirementsfor the auditorium. All or any required proportion of the return air canthus be directed through or around the air conditioning or dehumidifyingdevice.

- It will be obvious that various changes in the details, which havebeen hereindescribed and illustrated in order to explain the nature ofthe invention, may be made by those skilled in the art within theprinciple and scope of the inven- 1. The method of ventilating andattemperating a room in which people congregate and which is so designedwith seats that the people normally face the front or stage portion ofthe room, which comprises injecting air at a high velocity into the roomwell above the occupied section and people and in a direction toward thefront or stage portion of the room so as to avoid direct blasts into thesaid occupied section, and removing air from the lower or occupiedsection of the room at a plurality of points spaced in a directionforwardly and rearwardly of the room,

whereby the injected air will be mixed with and tempered by the warm airof the room while passing through the upper section thereof, and thetempered air mixture then circulated rearwardly at a lower velocity inthe lower occupied section of the room.

2. A ventilating and attemperating system for a room in which peoplecongregate, which comprises air conditioning apparatus, means for in-.jecting conditioned air from said apparatus at a high velocity into theupper space of said room and above the portion thereof occupied by thepeople, said injected air moving in a direction to avoid direct blastsinto the portion of the room occupied by the people, whereby theinjected conditioned airwill be first mixed with p and tempered by thewarm air of the room and circulated therewith in the space above theoccupied portion, means for removing portions of the circulated mixedair from the occupied porrection inwhich the conditioned air is injected1 into the room and in such .manner that strong drafts in the occupiedportion of the room will be avoided, and means for guiding desiredproportions of the air withdrawn from the room to said air conditioningapparatus for reconditioning and return to the room.

3. A ventilating and attemperating system for a room having 'arelatively deep space below the ceiling and above the lower section inwhich people congregate, which comprises a plurality of air outletsalong the length of the room and from said lower .section, said outletsarranged at different distances from one lateral wall of the room, ablower having its suction side connected to said outlets for withdrawingair from the room through said outlets, means connected to the outletside of the blower for conducting the withdrawn air to said room spaceand discharging it thereinto in jets adjacent the ceiling in a manner tocause an intimate mixture of the injected air with the air in said roomspace anda movement of the mixture through the room, and means fordehumidifying and cooling the withdrawn air before its return to theroom.

4. A ventilating and attemperating system for a room having a relativelydeep space below the ceiling and above the lower section in which peoplecongregate, which comprises a plurality of air outlets along the lengthof the room and from said lower section, said outlets arranged atdifferent distances from one lateral wall of the room, a blower havingits suction side connected to said outlets for withdrawing air from theroom through said outlet connections, means connected to the outlet sideof the blower for conducting the withdrawn air to said room space anddischarging it thereinto adjacent the ceiling in a jet and at arelatively high velocity and in a manner to cause an intimate mixture ofthe injected air'with the air in the room space and a movement of themixture through the room, means for admitting fresh outside air to theair column moving from the outlets to said room space, and means fordehumidifying more or less of the "air for admission into the room priorto its admission to said room space.

5. The method of ventilating and attemperating the air in a relativelydeep and large enclosure in which people congregate in considerablenumbers, which comprises discharging conditioned air, at a high velocityinto said enclosure in a direction to travel across the top of saidenclosure and be mixed with the air of the enclosure while moving bers,which comprises withdrawing air from the lower zone of said enclosure ata plurality of points spaced apart in one direction across said zone,conditioning air and discharging it into'said enclosure at a highvelocity in a direction to avoid direct blasts into said lower zone andtravel across the upper zone of the enclosure, whereby the high velocityconditioned air discharged into said enclosurewill mix with the air ofthe enclosure in said upper zone and cause a movement of the upperstrata of air of the enclosure across the upper part of the enclosureand then a descent of the air mixture and a gentle movement across andthrough the lower zone.

7. The method of ventilating and attemperating the air ina relativelydeep and large enclosure in which people congregate in considerablenumbers, which comprises withdrawing air from the lower zone of saidenclosure at a plurality of points spaced apart in one direction acrosssaid zone, conditioning air as to its temperature, humidity andfreshness, and discharging it into said enclosure at a high velocity ina direction to avoid direct blastsinto said lower zone and travel acrossthe upper zone of the enclosure, whereby the high velocity. conditionedair discharged into said enclosure will mix with air of the enclosure insaid upper zone and cause a move- -ment of the upper strata of air ofthe enclosure across the upper part of the enclosure and then a descentof the air mixture and a gentle movement across and through the lowerzone..

,8. The method of ventilating and attemperating the air in an enclosurein which people congregate and of the type having an occupied sectionwith seats arranged to face in the same direction,

direction in which the seats face, at a relatively high velocity andwell above the occupied section, and removing displaced air from theoccupied section at a plurality of points from front to rear to insurecirculation of the injected air forwardly through the upper section, andthen rearwardly at a lower velocity through the occupied section.

9. A ventilating and attemperating system for relatively largeenclosures, in the lower zone of which people may congregate, comprisingmeans including a nozzle for discharging air at a high velocity into theupper zone in a direction to travel across the enclosure first in saidupper zone, de-

scend and travel in a reverse direction through.

the occupied zone of said enclosure, and means for removing air fromsaid occupied zone at a plurality of points arranged along thedirection,

comprising injecting air into said enclosure in the for withdrawing airfrom the lower zone of said in one direction across the top of theenclosure,

and in the opposite directionthrough the occupied zone, and also cause atempering of the said discharged air by mixture with the air of theenclosure before its descent into and movement through the occupiedzone.

WILLIS H. CARRIER.

